Kirri, Talented Sprout, Waves of Aggression, and Klauth, Unrivaled Ancient

Prerequisites

• Kirri, Talented Sprout on the battlefield
• Waves of Aggression in the graveyard
• Klauth, Unrivaled Ancient on the battlefield
• You have at least one land card in your graveyard
• Klauth has power 5 or greater, or you control another creature with power 1 or greater that does not have summoning sickness
• An opponent cannot block and kill Klauth, or any other creature you may need to attack with

Steps

1. Declare Klauth and any other creature, if needed, as an attacker
2. Klauth triggers, adding at least that can only be spent to cast spells
3. At the beginning of your postcombat main phase, Kirri triggers, returning a land card from your graveyard to the battlefield
4. Cast Waves of Aggression from your graveyard for its retrace cost by paying and discarding a land card, causing you to untap all creatures that attacked this turn, and to get an additional combat and main phase after this one
5. Repeat

Results

• Infinite colored mana that can only be spent to cast spells
• Infinite combat phases
• Infinite magecraft triggers
• Infinite self-discard triggers
• Infinite storm count